Self-engaging, double-sided fastener products

ABSTRACT

A fastener product includes a base of plastic resin and a plurality of discrete fastener elements having stems of the plastic resin that are integrally molded with and extend from the base. The stems are arranged, as molded, in columns and rows with stems of some of the fastener elements projecting from a first surface of the base forming a first field of fastener elements and stems of other of the fastener elements projecting from an opposite, second surface of the base forming a second field of fastener elements. The fastener elements include engageable heads, with heads of the fastener elements forming the first field constructed to engage the heads of the fastener elements forming the second field to allow releasable fastening.

TECHNICAL FIELD

This invention relates to fastener products, and more particularly to flexible fastener products that can be wrapped about an object with one side of the product overlapping and releasably engaging an opposite side of the product.

BACKGROUND

Self-engaging fastener products, such as certain wraps and ties, are useful, for example, to close bags or to bundle objects. An example of a product capable of engaging itself is described by Kennedy et al., U.S. Pat. No. 5,260,015, which disclose providing loops on the back side of male fastener tape as the fastener tape substrate and elements are being formed, thus creating a composite fastener tape capable of fastening to itself.

SUMMARY

In aspects, the invention features a fastener product including self-engaging fastener elements having molded stems that extend integrally from opposite sides of a base.

In one aspect, the invention features a base of plastic resin and a plurality of discrete fastener elements having stems of the plastic resin. The stems are integrally molded with and extend from the base and are arranged, as molded, in columns and rows. The stems of some of the fastener elements extend from a first surface of the base forming a first field of fastener elements and stems of the other of the fastener elements project from an opposite, second surface of the base forming a second field of fastener elements. The fastener elements include engageable heads wherein heads of the fastener elements forming the first field are configured to engage the heads of the fastener elements forming the second field to allow releasable fastening.

In another aspect, the invention features a fastener product including a base formed of a degradable plastic resin and a plurality of discrete fastener elements having stems formed of the degradable plastic resin that extend from the base. The stems of some of the fastener elements project from a first surface of the base forming a first field of fastener elements and stems of the other of the fastener elements project from an opposite, second surface of the base forming a second field of fastener elements. The fastener elements include engageable heads formed of the degradable plastic resin, with the heads of the fastener elements forming the first field configured to engage the heads of the fastener elements forming the second field to allow releasable fastening.

In another aspect, the invention features a method of making a self-engaging fastener product. The method includes molding a flexible, plastic base having multiple, discrete fastener element stems of the plastic resin extending integrally from and molded with the base and arranged in columns and rows. The stems of some of the fastener elements projecting from a first surface of the base forming a first field of stems and stems of the other of the fastener elements projecting from an opposite, second surface of the base forming a second field of stems. Engageable heads are formed that extend outwardly from the stems forming fastener elements extending from the first and second surfaces. The heads of the stems in the first and second fields are configured to engage each other to allow releasable fastening.

Embodiments may include one or more of the following features. The base is of unitary structure of the plastic resin forming the first and second surfaces. In other embodiments, the base includes more than one layer. The layers can be adhered together by an adhesive layer.

In certain embodiments, the plastic resin is degradable, such as a biodegradable and/or compostable resin. The degradable resin may comply with ASTM D6400-99. Suitable degradable plastic resins include naturally derived polymers, polyactic acid and polyvinyl alcohol. In some cases, the degradable resin is formed of a standard commodity resin, such as polyethylene or polypropylene, with a degradable plastic additive included in the plastic matrix. In some embodiments, the fastener product is formed only of degradable plastic resin. The degradable resin can be selected such that it dissolves naturally within the human body. In some embodiments, the fastener product is a plant tie formed or, for example, a photo-degradable plastic resin.

In some embodiments, at least one of the first and second fields includes one or more discrete regions of fastener elements. In some cases, the fastener elements extend over a length of the fastener product. The fastener elements can have heads that overhang the base in one or more discrete directions, or the fastener elements can have heads that overhang the base in multiple directions. In some embodiments, the fastener elements projecting from at least one of the first and second broad surfaces are arranged in a band with a region adjacent the band free of the fastener elements. The fastener elements projecting from each of the first and second surfaces can be arranged in multiple, spaced-apart bands.

Methods can include continuously introducing molten resin to a gap defined adjacent a periphery of a rotating mold roll having an array of cavities for forming stems of fastener elements. The cavities extend inwardly from the mold roll periphery such that the resin at least partially fills the cavities to form stems extending from the first surface of the flexible base while excess resin forms at least part of the flexible base of the product. The resin is solidified and the solidified resin is stripped from the peripheral surface of the mold roll. In some cases, the method includes introducing molten resin to a gap defined between peripheral surfaces of a pair of rotating mold rolls each having an array of cavities for forming the stems. The cavities extend integrally from respective mold roll peripheries such that the resin at least partially fills the cavities to form stems extending from first and second surfaces of the base.

In some embodiments, the step of forming engageable heads includes deforming distal ends of stems extending from the first and second surfaces to form the fastener elements. In some cases, deforming distal ends of the stems includes deforming distal ends of stems extending from one of the first and second surfaces, then deforming distal ends of stems extending from the other of the first and second surfaces. In certain embodiments, deforming distal ends of the stems includes deforming distal ends of the stems extending from one of the first and second surfaces at a first deformation location, then deforming distal ends of the stems extending from the other of the first and second surfaces at a second deformation location that is spaced from the first deformation location. In some embodiments, deforming distal ends of the stems includes simultaneously deforming distal ends of stems of each of the first and second surfaces at a single deformation location. The distal ends of the stems can be deformed within a gap formed between a pair of opposing deformation rolls.

In some embodiments, molding the base with fastener element stems includes molding a first fastener preform and a second fastener preform, each of the fastener preforms including a base layer and an array of fastener element stems extending integrally therefrom. The method can include permanently affixing, e.g., with adhesive and/or within a nip, respective faces of the first and second fastener preforms in an opposing relationship to form the flexible base.

By forming a fastener product capable of self-engagement solely of moldable resin, e.g., in a continuous process, the fastener product can be formed inexpensively and efficiently. Because the fastener product can be formed of a single material, it can be formed entirely from materials, such as biodegradable materials or recyclable materials. These materials can be useful for applications where the user wants the fastener product to dissolve over time, for example, to bundle or tie produce or in medical applications. The fastener product is capable of self-engagement, e.g., without use of typically more expensive loop materials. By forming a base of unitary, solid construction, the need for an added process step of, e.g., adhesive lamination, can be eliminated. Also, a unitary, solid base can provide improved flexibility, e.g., because no adhesives and/or dissimilar materials are required. Molding the product to form discrete, point-like fastener elements tends to provide freedom in choosing a suitable cutting or trimming process to form the self-engaging fastener product.

The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a side view of a fastener product having self-engaging fastener elements.

FIG. 2 is a perspective view of the fastener product of FIG. 1.

FIG. 3 is a side view of the fastener product of FIG. 1 with engaged fastener elements.

FIG. 4 is a side view of a fastener element.

FIG. 5 is a top view of a fastener element arrangement.

FIG. 6 shows the arrangement of FIG. 5, with the fastener element stem outlines shown.

FIG. 7 is a diagrammatic view of a fastener product.

FIG. 8 illustrates a method and apparatus for making a fastener product.

FIG. 9 illustrates a method and apparatus for making a fastener product.

FIG. 10 is another embodiment of a fastener product having self-engaging fastener elements.

FIG. 11 illustrates a sheet of fastener products.

FIG. 12 shows an individual fastener product of FIG. 11 in use.

FIGS. 13 and 13A illustrate another fastener product embodiment in use.

FIGS. 14 and 14A illustrate the fastener product of FIG. 1 engaged to itself.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, a fastener product 10 in the form of a releasable strap includes a base 14 and two fields 20, 22 of mushroom-shaped fastener elements 12. Each field 20 and 22 of fastener elements 12 is arranged along a respective broad surface 16 and 18 of the base 14 and is capable of engaging the fastener elements 12 extending from the other of the surfaces 16, 18 for releasable fastening.

Each point-like fastener element 12 includes a stem 24 integrally molded with and extending generally perpendicularly from the base 14 to a distal head 26 that overhangs the base 14 on substantially all sides of the stem 24. Referring to FIG. 2 and also to FIG. 3, the fastener elements 12 of the fields 20, 22 are arranged in a pattern of rows and columns such that the fastener product 10 can be folded so as to overlap the two fields 20 and 22 of fastener elements 12 to engage the product 10 to itself (FIG. 3). The engaged fasteners can have a combined thickness “T” of less than about 2.0 millimeters, more preferably less than about 1.5 millimeters.

FIG. 4 shows a typical fastener element 12. In this illustrated example of a low profile fastener, molded stem 24 is of square cross-section with width W_(S) of about 0.007 to 0.012 inch (0.18 to 0.3 millimeter) and rises integrally from a near surface 16 of base 14. In some cases W_(S) is about 0.004 to 0.006 inch (0.09 to 0.15 millimeter). Base 14 is generally planar and can have a nominal thickness t_(b) of about 0.008 to 0.022 inch (0.2 to 0.56 millimeter). In certain embodiments t_(b) is about 0.004 to 0.011 inch (0.1 to 0.28 millimeter). Head 26 is typically formed of resin of molded stem 24 and is formed to overhang base 14, in a post-molding process, and is not itself of molded shape. However, a preferred head shape is one that overhangs the base on substantially all sides of stem 24 and has a thickness t_(h) of about 0.01 to 0.014 inch (0.25 to 0.36 millimeter). In some cases, t_(h) is about 0.005 to about 0.007 inch (0.13 to 0.18 millimeter). Produced by the forming methods outlined below and in U.S. Pat. No. 6,248,276 on a square stem, head 26 will generally be of circular or slightly oval footprint, with a major dimension W_(h) aligned in the direction of processing, of about 2.00 to 2.25 times stem thickness W_(S), or about 0.014 to 0.027 inch (0.56 to 0.76 millimeter) for preferred stem widths, or 0.007 to 0.014 inch (0.28 to 0.38 millimeters) in other preferred cases. In the example shown, head 26 is of circular cross-section and has a diameter W_(h) of about 0.0264 inch (0.671 millimeter). The overall thickness t_(f) of the fastener, including the base thickness and the height of the fastener elements, is about 0.052 to 0.071 inch (1.3 to 1.8 millimeters). In some embodiments, t_(f) is about 0.026 to 0.036 inch (0.65 to 0.9 millimeters). It should also be noted that in this embodiment, the upper surface of head 26 is generally flat over a central region “F” that covers the footprint of the underlying stem 16. Having such a relatively wide flat region can help an array of such fastener elements to readily slide across a mating array before engagement, such as to enable a user to position the fasteners after contact but prior to engagement. Flat upper surface regions also improve the feel of the array against skin by avoiding abrasiveness, and help to distribute normal loads against a mating surface during compression.

In a high profile example, square stem 24 width W_(S) is about 0.018 inch (0.46 millimeter), and major head dimension W_(h) is about 0.0378 inch (0.960 millimeters). In this high profile example, the overall thickness t_(f) of the fastener is about 0.040 to 0.115 inch (1.0 to 2.9 millimeters), with a base thickness of 0.008 to 0.020 inch (0.2 to 0.5 millimeter).

Other configurations are also possible. For example, some stems are inserted through the fastener base as separate elements, rather than being integrally molded of the same material. Such assembly processes can be more expensive, however, than integral molding. The stems may also be of different cross-section than square or rectangular. For example, some stems of circular cross-section can be molded integrally with the base on a roll having plates with aligned, half-cylinder grooves machined or etched into their side surfaces, with the grooves of each abutting plate aligned with those of the next to form cylindrical stem molding cavities. Fastener elements having crook-shaped heads are also contemplated. These heads can extend over the base in one or more discrete directions.

Referring next to FIG. 5, fastener elements 12 are arranged in repeating groups of three rows each. These rows are identified in the second row group from left as outer rows A and C and middle row B. The row spacing S_(r) within each row group is constant, and about 0.028 inch (0.71 millimeter) in this example, with middle row B disposed equidistant from rows A and C, such that rows A and C are separated by about 0.056 inch (1.14 millimeters). The fastener elements spacing S_(f) is constant along each row, and about 0.046 inch (1.17 millimeters) in this example. Each middle row B is longitudinally offset from its associated outer rows A and C, such that its fastener elements 12 are each disposed midway between adjacent fastener elements 12 in the outer rows. Each three row group is separated from the next three row group by a longitudinal track 28 clear of fastener elements. In this example, the pattern of row group and spacing has a repeat width W_(r) of about 0.114 inch (2.90 millimeters), just slightly greater than the repeat width that would be obtained by taking a full staggered array of row spacing S_(r) and removing every fourth row, and the heads 26 of the fastener elements are drawn at a nominal diameter of 0.0264 inch (0.671 millimeter), or an average of about 2.2 times the stem width.

The grouping of fastener element rows into three row groupings, each with a middle staggered row B and spaced from adjacent groups, can be particularly advantageous for self-engagement performance as it provides a sufficient bulk locking ratio at a particularly low head density. Each row group defines a longitudinal row of inter-element receptacles 30, each bounded by four fastener elements 12 and sized to receive and hold a fastener element head of a mating array on at least three sides. One such receptacle 30 is illustrated between four highlighted fastener elements, with the dashed outline of a fastener element head 26′ engaging between the highlighted fastener elements. Given the above inter-row spacing, inter-element spacing and head diameters, the clearance C₁ between adjacent heads along each row is about 0.02 inch (0.5 millimeter), or slightly less than the nominal head diameter, while the clearance C₂ between transversely aligned fastener elements is about 0.03 inch (0.75 millimeter), or slightly greater than the nominal head diameter. Thus, a mating fastener element head 26′ need only laterally deflect one fastener element of middle row B during engagement.

FIG. 6 also shows the cross-sectional area of the square stem 24 of each fastener element 12, and shows in dashed outline the thickness of the molding and spacer plates of the mold roll employed to form the base and stems of the fastener. As can be seen in this view, the minimum corner separation S_(s) between the stems 24 of adjacent fastener elements in middle and outer rows of each row grouping, is less than the nominal diameter of the fastener element heads, such that a trapped fastener element head 26′ (FIG. 5) is obstructed from moving laterally from its receptacle 30 in any direction, once engaged. Thus, each locked head is trapped in a cage formed by four adjacent fastener element stems 24. In this example, stem corner separation S_(s) is about 0.0194 inch (0.49 millimeter), significantly less than the nominal head diameter of 0.0264 inch (0.671 millimeter).

Fastener elements having the above dimensions and arranged in the pattern of FIG. 5 provide an overall head density of 585 hooks per square inch (91 hooks per square centimeter), and a head density of about 29.2 percent. The bulk engagement, locking and overlap ratios were calculated to be 228 percent, 25.4 percent, and zero percent, respectively.

In a high profile example of the pattern of FIG. 5, the labeled dimensions are 0.069 inch (1.75 millimeters) for S_(f), 0.176 inch (4.47 millimeters) for W_(r), and 0.044 inch (1.1 millimeters) for S_(r), with a stem corner separation S_(S) of about 0.0308 inch (0.78 millimeter).

Other patterns are contemplated. For example, the patterns described above may be scaled up or down (e.g., scaled down by one-half). Examples of suitable patterns are described in U.S. Pat. No. 6,687,962, the entire contents of which are incorporated herein by reference.

The field of fastener elements 12 can extend along the entire length L of the fastener product 10, as shown by FIG. 1, or, alternatively, the field of fastener elements 12 can be limited to or formed of discrete regions, such as regions 34, 36, 38 and/or 40 of FIG. 7. Referring now to FIG. 7, there can be one region of fastener elements 12 extending along a respective surface 16, 18 or there can be multiple, spaced apart regions of fastener elements (not shown) extending along a respective surface. The fastener elements 12 of any two regions (or more, if applicable) can be formed to engage each other by overlapping the regions. Similarly, as shown by FIGS. 14 and 14A, fastener elements 12 of a single field 20, 22 can be formed and arranged to engage fastener elements 12 of the same field 20, 22. As shown, the fastener product 10 is folded such that fastener elements 12 of field 20 engage other fastener elements 12 of field 20.

FIG. 8 illustrates a method and apparatus, utilizing methods and apparatus described by U.S. Pat. No. 4,794,028, the contents of which are incorporated by reference, for forming the fastener product of FIG. 1 having a solid base of unitary structure (i.e., formed by a single layer) using a continuous molding process. In this embodiment, a fastener sheet 55 is formed by continuously introducing molten resin 42 to a pair of counter-rotating mold rolls 44 and 48 in a nip 46 between the mold rolls 44 and 48. Resin 42 introduced into the nip 46 at least partially fills the cavities extending from the peripheries of the rolls 44 and 48. As an alternative, resin can be introduced directly and separately to each of rolls 44 and 48 at a location upstream of the nip 46 by a pair of extruders, e.g., that extrude the resin at a pressure sufficient to at least partially fill the mold cavities of each of rolls 44 and 48. The resin is solidified within the cavities 50 of roll 48 such that it can be stripped from the cavities forming stems 24 as the resin travels about roll 44. While on roll 44, immediately before encountering head-forming roll 76, the distal ends of the stems 24 are rapidly heated, either by a flame 58 as shown, or by a heated platen. The molten ends are then deformed at a deformation location 59 by rotating roll 76 that is kept at a temperature lower than that of the incoming stem ends. Stems molded with a height of 0.076 inch (1.9 millimeters), for example, are deformed in one embodiment to a final height of about 0.050 inch (1.3 millimeters), with relatively flat upper head surfaces. More details of this process can be found in U.S. Pat. No. 6,248,276, the entire contents of which are incorporated herein by reference. After deformation of the stems extending from the one surface, resin is stripped from cavities 50 of roll 44. The distal ends of the remaining stems 24 are heated and, at a second deformation location 57 spaced from the first deformation location 59, deformed by roll 56, as described above. As an alternative to using rolls 76 and 56 to sequentially form heads 26, distal ends of the stems 24 can be deformed sequentially at spaced-apart locations 57 and 63 downstream of mold roll 44, e.g., using deformation roll 73 and heater 61 (both shown by dashed lines). Also, stems 24 can be deformed at one in-line location (e.g., location 57) and the other, undeformed stems 24 can be deformed later in a separate, off-line process, or the stems 24 of both sides may be deformed off-line at sequential locations. Fastener products (e.g., fastener straps, bundle ties and wrap ties) can then be formed by cutting molded sheet 55 into discrete lengths (and/or widths), as described in greater detail below.

FIGS. 8 and 9 illustrate an alternative method and apparatus for forming a fastener product 100 shown by FIG. 10. Referring to FIG. 8, a fastener preform 52 (FIG. 9) is formed by continuously introducing molten resin 42 to the mold roll 44, either in the nip 46 between the mold roll 44 and a counter-rotating pressure roll 48 that is free of mold cavities, or directly with a pressurized shoe (not shown). The resin 42 is forced into the array of cavities 50 and cooled on roll 44 to form stems 24 extending integrally from a side of a sheet of resin that cools on the surface of roll 44 before being stripped from roll 44 and passed about roll 53. Surface 60 opposite the stems 24 is free of the fastener elements 12 (see FIG. 9). While on roll 54, immediately before encountering head-forming roll 56, the distal ends of the stems 24 are rapidly heated, either by a flame 58 as shown, or by a heated platen, keeping the remainder of the stems 24 and base sheet relatively cool. The molten ends are then deformed at location 57, as described above, to form a fastener preform 52.

Referring now to FIG. 9, two fastener preforms 52 a and 52 b are directed to a nip 64 defined between two pressure rolls 63 to laminate the two fastener preforms 52 a and 52 b face-to-face at their surfaces 60. Adhesive 62 is applied to fastener preform 50 b prior to the nip 64 and pressure is applied to the fastener preforms 52 a and 52 b to permanently affix the preforms together such that the fastener elements 12 extend from opposite surfaces 66, 68 of a base 70 formed by two resin sheet layers 72, 74 (FIG. 10). In some embodiments, adhesive is not applied. Other means can be used to adhere the fastener preforms together, such as heat (e.g., by flame).

The fastener preforms 52 a and 52 b can be directed to the nip 64 as part of the continued molding and forming process described above with reference to FIG. 8. Alternatively, as an example, the preforms 52 a and 52 b can be directed to the nip 64 from one or more storage rolls (not shown).

Fastener products can be formed by, e.g., die cutting, rotary cutting and/or perforating sheet 55 along predetermined boundaries. Preferably, the preform sheet 55 is cut and/or perforated such that multiple, interconnected straps can be packaged on a continuous roll and, for example, later separated by hand and/or by machine. In some cases, the sheet 55 is cut (e.g., by rotary cutting) into individual fastener products and, for example, packaged loose in a box or a bag. For example, referring to FIG. 11, sheet 90 includes multiple, nested fastener straps 92 formed by perforating the sheet 90 (e.g., by die cutting) along lines 94. Each strap 92 can be separated from the sheet 90 by pulling an individual strap 92 in a direction that separates the strap 92 from the adjacent straps 92. Cutting a sheet to form nested fastener straps is described in greater detail in U.S. Pat. No. 6,044,525, the contents of which are hereby incorporated by reference. The individual strap 92 can then be used to bundle multiple objects, as is shown by FIG. 12, by inserting a tail portion 96 of the strap 92 into an opening 98 in a head portion 100. End 102 can be free of the fastener elements 12 to facilitate grasping the strap 92, e.g., to disengage the engaged fastener elements 12.

As noted above, the fastener product can be formed of a single material, such as polyethylene or polypropylene. Typically, loop materials are the more expensive component of a hook and loop fastener, thus self-engaging, double-sided fastener products formed completely of, for example, an inexpensive polyethylene or polypropylene may be relatively inexpensive compared to straps requiring loop materials. The above-described fastener products can be used, for example, to bundle cord, hoses, wires or any other application for which a bundle tie or strap may be useful.

Referring now to FIGS. 13 and 13A, a self-engaging fastener product in the form of a plant tie 110 is used to secure a grape vine 112 to a tube trellis 114. The plant tie 110 is formed (e.g., by the process described above with reference to FIG. 8) of a single, biodegradable or compostable plastic, e.g., a plastic meeting the ASTM D6400-99 standard, which is hereby incorporated by reference as if fully set forth herein. The material can be selected to produce a controlled product lifetime. In other words, the material can be selected to reliably degrade completely within a predetermined time period, such as months or years, depending on the application. The degradable material can also be selected to degrade in landfills, photo-degrade, etc. Suitable biodegradable or compostable plastics include naturally derived polymers, polyactic acid and polyvinyl alcohol (PVAL), such as ELVANOL brand made by DuPont. Commodity resins, such as polypropylene and polyethylene, can also be used where a suitable degradable plastic additive has been added to the resin matrix. Suitable degradable plastic additives include those produced by Environmental Products Inc., located at Conroe, Tex.

Self-engaging, degradable fastener products can also be formed, e.g., using the process described above with reference to FIG. 8, for use in medical applications. For example, a fastener product formed only of polyactic acid, which is naturally dissolvable by the body, may be used, e.g., during surgery to position or bind internal organs or other parts of the body. If desired, the fastener product can be left in the body where it will be dissolved.

A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, other fastener product configurations are contemplated such as those described by U.S. Provisional Application 60/547,212, filed Feb. 24, 2004 titled “Fastener Products”, the contents of which are hereby incorporated by reference as if fully set forth herein. Accordingly, other embodiments are within the scope of the following claims. 

1. A fastener product comprising: a base of plastic resin; and a plurality of discrete fastener elements having stems of the plastic resin that are integrally molded with and extend from the base arranged, as molded, in columns and rows, the stems of some of the fastener elements projecting from a first surface of the base forming a first field of fastener elements and stems of other of the fastener elements projecting from an opposite, second surface of the base forming a second field of fastener elements; the fastener elements including engageable heads wherein heads of the fastener elements forming the first field are configured to engage the heads of the fastener elements forming the second field to allow releasable fastening.
 2. The fastener product of claim 1, wherein the base comprises a unitary structure of the plastic resin, the unitary structure defining the first and second surfaces.
 3. The fastener product of claim 1, wherein the base comprises more than one layer.
 4. The fastener product of claim 3, wherein the layers are adhered together by an adhesive layer.
 5. The fastener product of claim 1, wherein at least one of the first and second fields of fastener elements comprises one or more discrete regions of fastener elements.
 6. The fastener product of claim 1, wherein the fastener elements of at least one of the first and second fields extend over a length of the fastener product.
 7. The fastener product of claim 1, wherein the fastener elements have heads that overhang the base in one or more discrete directions.
 8. The fastener product of claim 1, wherein the fastener elements have heads that overhang the base in multiple directions.
 9. The fastener product of claim 1, wherein fastener elements projecting from at least one of the first and second surfaces are arranged in a band with a region adjacent the band free of the fastener elements.
 10. The fastener product of claim 9, wherein the fastener elements projecting from each of the first and second surfaces are arranged in multiple, spaced-apart bands.
 11. The fastener product of claim 1, wherein the plastic resin is a biodegradable or compostable material.
 12. The fastener product of claim 11, wherein the plastic resin complies with ASTM D6400-99.
 13. The fastener product of claim 1, wherein the plastic resin is selected from a group consisting of naturally derived polymers, polyactic acid and polyvinyl alcohol.
 14. The fastener product of claim 1, wherein the plastic resin comprises a degradable plastic additive.
 15. A fastener product comprising: a base comprising degradable plastic resin; and a plurality of discrete fastener elements having stems of the degradable plastic resin that extend from the base, the stems of some of the fastener elements projecting from a first surface of the base forming a first field of fastener elements and stems of other of the fastener elements projecting from an opposite, second surface of the base forming a second field of fastener elements; the fastener elements including engageable heads formed of the degradable plastic resin wherein heads of the fastener elements forming the first field are configured to engage the heads of the fastener elements forming the second field to allow releasable fastening.
 16. The fastener product of claim 15, wherein the degradable plastic resin complies with ASTM D6400-99.
 17. The fastener product of claim 15, wherein the degradable plastic resin is selected from a group consisting of naturally derived polymers, polyactic acid and polyvinyl alcohol.
 18. The fastener product of claim 15, wherein the degradable plastic resin comprises a standard commodity resin and a degradable plastic additive.
 19. The fastener product of claim 15, wherein the base comprises a unitary structure of the plastic resin, the unitary structure defining the first and second surfaces.
 20. The fastener product of claim 15, wherein the base comprises more than one layer.
 21. The fastener product of claim 20, wherein the layers are adhered together by an adhesive layer.
 22. The fastener product of claim 15 consisting of the degradable plastic resin.
 23. The fastener product of claim 22, wherein the degradable plastic resin dissolves naturally in a human body.
 24. The fastener product of claim 23, wherein the degradable plastic resin comprises polyactic acid.
 25. The fastener product of claim 22 in the form of a plant tie.
 26. The fastener product of claim 25, wherein the degradable material is photo-degradable.
 27. A method of making a self-engaging fastener product, the method comprising: molding a flexible, plastic base of plastic resin having multiple, discrete fastener element stems of the plastic resin extending integrally from and molded with the base and arranged in columns and rows, the stems of some of the fastener elements projecting from a first surface of the base forming a first field of stems and stems of other of the fastener elements projecting from an opposite, second surface of the base forming a second field of stems; and forming engageable heads extending outwardly from the stems forming fastener elements extending from the first and second surfaces, the heads of stems in the first and second fields being configured to engage each other to allow releasable fastening.
 28. The method of claim 27, wherein the step of molding comprises continuously introducing molten resin to a gap defined adjacent a periphery of a rotating mold roll having an array of cavities for forming stems of fastener elements, the cavities extending inwardly from the mold roll periphery, such that the resin at least partially fills the cavities to form stems extending integrally from the first surface of the flexible base while excess resin forms at least part of the flexible base of the product; solidifying the resin; stripping the solidified resin from the peripheral surface of the mold roll.
 29. The method of claim 27, wherein the step of forming engageable heads comprises deforming distal ends of the stems extending from the first and second surfaces to form the fastener elements.
 30. The method of claim 29, wherein deforming distal ends of the stems comprises deforming distal ends of stems extending from one of the first and second surfaces, then deforming distal ends of stems extending from the other of the first and second surfaces.
 31. The method of claim 30, wherein deforming distal ends of the stems comprises deforming distal ends of stems extending from one of the first and second surfaces at a first deformation location, then deforming distal ends of stems extending from the other of the first and second surfaces at a second deformation location that is spaced from the first deformation location.
 32. The method of claim 31, wherein at least one of the first and second deformation locations comprise a gap formed between opposing rolls.
 33. The method of claim 29, wherein deforming distal ends of the stems forms fastener elements having heads that extend laterally from the stems in multiple directions.
 34. The method of claim 27, wherein the step of molding comprises continuously introducing molten resin to a gap defined between peripheral surfaces of a pair of rotating mold rolls each having an array of cavities for forming the stems, the cavities extending inwardly from respective mold roll peripheries, such that the resin at least partially fills the cavities to form stems extending from the first surface and the opposite, second surface of the flexible base while excess resin forms the flexible base of the product; solidifying the resin; stripping the solidified resin from the peripheral surfaces of the mold rolls.
 35. The method of claim 27, wherein the step of molding comprises molding a first fastener preform and a second fastener preform, each of the fastener preforms including a base layer and an array of fastener element stems extending integrally therefrom.
 36. The method of claim 35 comprising permanently affixing respective faces of the first and second fastener preforms in an opposing relationship forming the flexible base.
 37. The method of claim 36, wherein the step of affixing comprises adhering the faces with adhesive.
 38. The method of claim 37, wherein the step of affixing comprises introducing the first and second fastener preforms to a nip.
 39. The method of claim 27, wherein at least one of the first and second fields of stems comprise one or more discrete regions of stems.
 40. The method of claim 27, wherein stems extending from at least one of the first and second surfaces are arranged in a band with a region adjacent the band free of the stems.
 41. The method of claim 40, wherein the stems extending from at least one of the first and second surfaces are arranged in multiple, spaced-apart bands.
 42. The method of claim 27, wherein the fastener elements include heads that extend laterally from stems in multiple directions.
 43. The method of claim 27, wherein the fastener elements include heads that extend laterally from stems in one or more discrete directions.
 44. The method of claim 27, wherein the plastic resin comprises a degradable material.
 45. The method of claim 44, wherein the degradable material is selected from a group consisting of naturally derived polymers, polyactic acid and polyvinyl alcohol.
 46. The method of claim 44, wherein the plastic resin complies with ASTM D6400-99.
 47. The method of claim 27 further comprising introducing a degradable plastic additive to the plastic resin prior to molding. 